Śrīmad-Bhāgavatam · Text 11.21.20
Who is speaking and story frame
कलेर्दुर्विषह: क्रोधस्तमस्तमनुवर्तते ।
तमसा ग्रस्यते पुंसश्चेतना व्यापिनी द्रुतम् ॥ २० ॥
kaler durviṣahaḥ krodhas
tamas tam anuvartate
tamasā grasyate puṁsaś
cetanā vyāpinī drutam
From quarrel arises intolerable anger, followed by the darkness of ignorance. This ignorance quickly overtakes a man’s broad intelligence.
Read the purport on Vedabase.ioFrom Canto 10, chapter 14 onward, the translation and purports were completed by Śrīla Prabhupāda's disciples after his departure, and published by the Bhaktivedanta Book Trust.